Coloured or black particles

Abstract

This invention relates to a process for the preparation of a dispersion comprising coloured or black particles, such coloured or black particles prepared by the process, the use of the dispersion and the coloured or black particles in electrophoretic fluids, and electrophoretic display devices comprising such fluids.

We claim: 
     
         1 . A dispersion consisting of;
 1) at least one non-polar perfluorinated solvent, colored or black particles consisting of at least one dye, optionally at least one light stabilizer, and at least one fluorinated surfactant, and optionally at least one polymer selected from poly(vinyl pyrrolidone), poly(acrylamide), poly(acrylic acid), and poly(methacrylic acid), or   2) at least one non-polar non-fluorinated hydrocarbon solvent, and colored or black particles consisting of at least one dye selected from Direct Black 22, Acid Black 52, Acid Black 132, Acid Black 107, Acid Black 172, Solvent Black 27, and Solvent Black 29, optionally at least one light stabiliser, and at least one surfactant,   wherein the dispersion 1) and 2) optionally includes at least one dye which is soluble in a non-polar solvent.   
     
     
         2 . The dispersion according to  claim 1 , wherein the colored or black particles consist of at least one dye, optionally at least one light stabiliser, at least one poly(hexafluoropropylene oxide) polymeric surfactant with a monofunctional carboxylic acid end group and a weight-average molecular weight Mw between 5000 and 8000, and optionally poly(vinyl pyrrolidone) and/or poly(acrylic acid). 
     
     
         3 . An electronic device comprising a dispersion of  claim 1 , wherein the electronic device is selected from the group consisting of an electrooptical device, electrochemical device, electrophotographic device, electrowetting device, electro-osmotic device, electrohydrodynamic device, and electrophoretic device. 
     
     
         4 . The device according to  claim 3 , the device selected from the group consisting of a dynamic keypad, e-paper watch, dynamic pricing and advertising device, e-reader, rollable display, smart card media, product packaging, mobile phone, lab top, display card, digital signage and shelf edge label. 
     
     
         5 . The device according to  claim 3 , wherein the dispersion is applied to the device by a technique selected from inkjet printing, slot die spraying, nozzle spraying, and flexographic printing. 
     
     
         6 . The dispersion according to  claim 1 , wherein the colored or black particles consist of at least one dye, optionally at least light stabiliser, and at least one fluorinated surfactant, and the at least one dye is selected from the group consisting of Solvent Blacks: 1, 8, 18, 25, 27, 29, 33, 36, 37, 38, 40, 45, 48, 51; Disperse Blacks: 10 Acetate, 12 Acetate, 13, 28 Acetate, 28 Polyester, 29 Acetate, 29 Polyester, 30; Direct Blacks: 22, 52, 53, 54, 58, 59, 60, 61, 62, 63, 64, 69, 71, 88, 89, 91, 92, 94, 95, 97, 98, 101, 102, 104, 107, 108, 109, 112, 113, 114, 116, 117, 118, 121, 122, 124, 125, 127, 128, 129, 130, 132, 133, 134, 137, 140, 142, 143, 144, 145, 146, 147; Acid Blacks: 1, 24, 84, 52, 107, 132, 172; Acid Reds: 1, 106, 114, 129, 249, 315, 336; Acid Greens: 27, 16; Acid Blues: 25, 80, 83, 113, 185, 324; Acid Violets: 17, 48; and Acid Yellows: 17, 29, 79, 127, 151, 220. 
     
     
         7 . The dispersion according to  claim 1 , wherein the colored or black particles consist of at least one dye, optionally at least light stabiliser, and at least one fluorinated surfactant, and the at least one dye is selected from the group consisting of Acid Red 37, Acid Fuchsine, Solvent Blue 35, Solvent Black 27, Solvent Black 29, Solvent Black 34, Acid Black 52, Acid Black 107, Acid Black 132, Acid Black 172, Acid Black 194, Acid Black 211, Acid Black 222, Direct Black 19, Direct Black 22, Direct Black 51, Direct Black 80, and Direct Black 112. 
     
     
         8 . The dispersion according to  claim 1 , wherein the colored or black particles consist of at least one dye, optionally at least light stabiliser, and at least one fluorinated surfactant, and the at least one dye is selected from the group consisting of Direct Black 22, Acid Black 52, Acid Black 132, Acid Black 107, Acid Black 172, Solvent Black 27, Solvent Black 29, Acid Red 37, and Acid Fuchsine. 
     
     
         9 . The dispersion according to  claim 1 , wherein the colored or black particles consist of at least one dye, optionally at least light stabiliser, and at least one fluorinated surfactant, and the at least one dye is selected from the group consisting of Direct Black 22, Acid Black 52, Acid Black 132, Acid Black 107, Acid Black 172, Solvent Black 27, and Solvent Black 29.